THE FUNCTION OF THE UNJUST ENRICHMENT PRINCIPLE

(A) POSSIBLE FUNCTIONS OF THE UNJUST ENRICHMENT PRINCIPLE

Now it has been recognized that there is a principle of unjust enrichment in English law, it is necessary to determine the function of that principle. It can be interpreted as having two alternative functions, which can usefully be called the ‘formulaic’ and the ‘normative’ functions.

(i) The Formulaic Function

According to the formulaic function, the defendant will only be considered to have been unjustly enriched where the circumstances of the case satisfy the formula for unjust enrichment, namely that the defendant has received an enrichment at the expense of the claimant and in circumstances which fall within one of the recognized grounds of restitution. Crucially, restitutionary relief will only be available to the claimant according to this interpretation of the principle if restitutionary liability has previously been recognized in similar circumstances.

(ii) The Normative Function

According to the normative function of the principle, the defendant can be considered to have been unjustly enriched whenever the court considers that the circumstances of the enrichment were unjust. The normative function is much more discretionary, involving the judge considering the facts of the case without regard to whether restitutionary relief has previously been awarded in similar circumstances.^[1]

• [1] For an extreme version of the normative approach see H Dagan, The Law and Ethics of Restitution(Cambridge: Cambridge University Press, 2004), who adopts a ‘contextual normative inquiry’ to the law ofunjust enrichment, 36. Consequently, for Dagan the unjust enrichment principle does not have a unifyingfunction because the appropriate result depends on the particular context of the case.